We developed here a green procedure for the synthesis of novel N–doped bio-graphenes from Arabic gum as a natural source by using different N-dopants (urea, hexamethyleneteramine, and ethylenediamine) and Gelatin as a carbon source containing N species. The effect of these dopants on the type of nitrogen species, nitrogen contents, and surface structure of graphene catalysts was investigated on their catalytic properties for oxidative removal of sulfur compounds in fuel oil. All of doped graphenes show the pyridinic and pyrrolic nitrogen species, while the graphene doped with hexamethylenetetramine shows the highest amount of nitrogen with some content of amine group as well as pyridinc-N and pyrrolic-N. This N-doped graphene indicates the highest catalytic activity due to the type of nitrogen species, higher nitrogen content, and higher surface area. The resulting immobilized catalysts with MoO₃ also show the similar trend in catalytic activities. Nitrogen doping increase the electron density of peroxo groups by donating electrons to Mo-centers which enhance the catalytic activity by decreasing the oxidation barrier.